A number of other factors also contributed to the United States' decision to enter World War I:
German submarine warfare: Germany's unrestricted submarine warfare campaign, which targeted merchant ships as well as warships, led to the deaths of thousands of people and disrupted global trade. The sinking of the Lusitania was just one of many incidents that contributed to growing anger in the United States about Germany's actions.
British propaganda: The British government launched a massive propaganda campaign in the United States in order to win support for its war effort. This campaign was successful in shaping public opinion in the United States and helping to turn Americans against Germany.
Zimmerman telegram: In early 1917, the British intercepted a telegram from the German Foreign Secretary, Arthur Zimmermann, to the German ambassador in Mexico. The telegram proposed an alliance between Germany and Mexico in the event of war between the United States and Germany. The release of the Zimmerman telegram caused outrage in the United States and further solidified support for intervention in the war.
In addition to these factors, there were also a number of economic and political considerations that influenced the United States' decision to enter World War I. The United States was heavily invested in the Allied cause, and a German victory would have had a devastating impact on the American economy. Additionally, the United States was concerned about the potential for Germany to become a global superpower and was eager to prevent this from happening.
The United States entered World War I on April 6, 1917, following a declaration of war by Congress. The American entry into the war helped to turn the tide in favor of the Allies, and the war ended in an Allied victory in 1918.